Chip surface height measurement method, device, equipment and storage medium

Abstract

The application relates to a chip surface height measurement method, device and equipment and a storage medium, which are applied in the field of semiconductor technology and include the following steps: controlling a laser emitting unit to emit a laser line to a position where a chip is located at a preset angle; controlling an image acquisition unit to collect chip image information, wherein the chip image information comprises a laser line image; selecting a laser line calculation area in the laser line image and calculating a centroid position of the laser line calculation area; establishing a chip height measurement equation according to the corresponding relationship between the laser line and a height calibration unit; and substituting the centroid position into the chip height measurement equation to obtain the chip surface height. The application has the technical effect of realizing non-contact measurement of the chip surface height and improving the accuracy of the chip surface height measurement.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a method, apparatus, device and storage medium for measuring the surface height of a chip. Background Technology

[0002] In semiconductor chip mounting, dispensing and chip mounting are two critical processes. Errors in the equipment's structure and the dimensional variations of the materials can make it difficult for the equipment to accurately measure the real-time height of the chip substrate surface or the chip mounting surface. This can lead to quality issues such as inaccurate dispensing volume, incomplete dispensing patterns, large deviations in chip mounting height, and chip breakage. Specifically, when chips are mounted on the substrate surface, the height of all mounted chips is measured; when no chips are mounted on the substrate surface, the height of the chip substrate surface is measured.

[0003] Currently, there are automatic measurement methods based on motor torque control for measuring the height of chip substrate surfaces. Based on a set torque, when the structure moves and touches the contact surface, the corresponding position is recorded when the torque reaches the set value, thereby realizing automatic height measurement. However, the torque-based measurement method is a contact measurement method. When the measured height is high, the torque may cause some damage to the chip substrate structure, especially for ultra-thin substrates with a thickness of less than 0.15mm. Summary of the Invention

[0004] To help address the problem that contact measurement methods may damage the chip substrate structure, this application provides a chip surface height measurement method, apparatus, device, and storage medium.

[0005] In a first aspect, this application provides a method for measuring the height of a chip surface, employing the following technical solution: the method is applied to a chip surface height measurement system, the chip surface height measurement system comprising: an image acquisition unit for acquiring image information, a laser emission unit for emitting laser lines, and a height calibration unit for calibrating height; the method comprising:

[0006] The laser emitting unit is controlled to emit a laser line to the location of the chip at a preset angle.

[0007] The image acquisition unit is controlled to acquire chip image information, including laser line images;

[0008] Select the laser line calculation region in the laser line image and calculate the centroid position of the laser line calculation region;

[0009] Substituting the centroid position into the chip height measurement equation yields the chip surface height.

[0010] The above technical solution involves controlling the laser emitting unit to emit a laser line onto the chip, and then using the image acquisition unit to acquire the image information of the laser line at the location of the unit. After selecting the area, the surface height of the chip can be calculated using the chip height measurement equation. By combining image and laser, the measurement equipment does not need to be in direct contact with the chip substrate, thus enabling non-contact measurement of the chip surface height, which helps to reduce damage to the chip substrate.

[0011] In one specific implementation, the chip surface height measurement system further includes: a plane calibration unit for calibrating the plane position, and the steps for establishing the chip height measurement equation include:

[0012] Based on the calibration position of the image acquisition unit, a position transformation equation is established with the correspondence between the calibration position and the standard position of the plane calibration unit;

[0013] The image acquisition unit obtains the preset actual position;

[0014] The measurement standard position of the image acquisition unit is obtained based on the preset actual position and the position transformation equation;

[0015] At the standard measurement position, the laser emitting unit is controlled to emit a laser line toward the calibration surface of the height calibration unit at the preset angle;

[0016] The image acquisition unit is controlled to acquire an image of the laser line;

[0017] In the image of the laser line, several calibration regions of the laser line are selected, and the centroid positions of the several calibration regions are calculated;

[0018] The three-dimensional coordinates of the centroid of the calibration area are calculated based on the centroid position of the calibration area and the preset coordinate calculation equation.

[0019] The chip height measurement equation is generated by fitting the three-dimensional coordinates of the centroids of several calibration regions using the Gaussian plane equation.

[0020] The above technical solution involves transforming the coordinate system of the image acquisition unit and correcting its position, enabling the unit to acquire image information in a reference coordinate system. This improves the accuracy of image information acquisition and consequently enhances the accuracy of chip surface height measurement. A laser line is emitted from the laser emission unit at the standard position of the image acquisition unit, and the centroid of the laser line on the standard height calibration unit is obtained. This allows for the calculation of the actual height of the laser line on the calibration surface. A height measurement equation is then generated by fitting the actual position of the laser line on the height calibration unit, facilitating the calculation of chip surface height in practical applications. In practical applications, the laser emission unit calibration eliminates the need for direct contact between the measuring device and the chip substrate, enabling non-contact measurement and reducing the risk of damage to the chip substrate.

[0021] In one specific implementation, the chip surface height measurement system further includes: a driving unit for driving the image acquisition unit and the laser emission unit to move synchronously, and the calibration surface includes calibration surfaces of different heights;

[0022] After calculating the three-dimensional coordinates of the centroid of the calibration region based on the centroid position of the calibration region and a preset coordinate calculation equation, the method further includes:

[0023] The driving unit is controlled to move the image acquisition unit and the laser emission unit sequentially.

[0024] The laser emitting unit is controlled to emit laser lines at preset angles on calibration surfaces at different heights;

[0025] The image acquisition unit is controlled to acquire images of the laser line at different heights on the calibration surface;

[0026] In the image of the laser line, several calibration regions of the laser line are selected, the centroid positions of several calibration regions are calculated, and multiple sets of centroid positions of the calibration regions at different heights are obtained.

[0027] The three-dimensional coordinates of the centroid of the calibration area are calculated based on the centroid position of the calibration area and the preset coordinate calculation equation, and multiple sets of three-dimensional coordinates of the centroid of the calibration area are generated on the calibration surface at different heights.

[0028] The chip height measurement equation is generated by fitting the three-dimensional coordinates of the centroids of multiple calibration regions using the Gaussian plane equation.

[0029] Through the above technical solution, the height calibration unit includes multiple calibration surfaces with different heights. By moving the laser emitting unit, a laser line is emitted from the calibration surfaces at different heights, capturing multiple sets of calibration areas and calculating the actual position of the centroid of the calibration area. The actual position is used to fit and generate a height measurement equation, which can be used to calculate the chip surface height in practical applications. By calculating the fitting equation at the centroid positions of the multiple calibration surfaces at different heights in the height calibration unit, the fitted equation results can be closer to the actual situation, improving the accuracy of chip surface height measurement in practical applications.

[0030] In one specific implementation, establishing a position transformation equation based on the correspondence between the calibration position of the image acquisition unit and the standard position of the calibration position in the planar calibration unit includes:

[0031] Obtain the calibration position of the image acquisition unit;

[0032] The image acquisition unit is controlled to acquire the plane calibration information of the plane calibration unit, and the plane calibration information includes the standard position corresponding to the calibration position of the image acquisition unit;

[0033] The position transformation equation is generated based on the calibration position of the image acquisition unit and the standard position corresponding to the calibration position.

[0034] By establishing a transformation equation to link the actual coordinates of the camera with the reference coordinates of the plane calibration unit, the above technical solution enables measurement and position calculation to be performed in a standard reference coordinate system in subsequent measurements, which can help to make the chip surface height measurement more accurate.

[0035] In one specific implementation, before controlling the laser emitting unit to emit a laser line to the chip location at a preset angle, the method further includes:

[0036] The image acquisition unit acquires the actual measured position of the chip in the chip image.

[0037] According to the position conversion equation, the actual measured position of the chip is converted into the standard measured position of the chip;

[0038] The step of controlling the laser emitting unit to emit a laser line to the chip location at a preset angle includes:

[0039] At the chip measurement standard position, the laser emitting unit is controlled to emit a laser line to the chip location at a preset angle.

[0040] By using the above technical solution, when actually measuring the height of the chip surface, the position of the image acquisition unit is calibrated using the position transformation equation before laser measurement. This ensures that the coordinates of the image acquisition unit are in the standard reference coordinate system after each movement, which makes the final measured height result more accurate and improves the precision of chip surface height measurement.

[0041] In one specific implementation scheme, the preset coordinate calculation equation includes:

[0042] z = x · tanθ

[0043] Where x represents the abscissa of the centroid of the calibration area, θ is the angle between the laser line and the calibration surface, and z is the actual height of the centroid of the calibration area in the height calibration unit.

[0044] In one specific implementation, the position transformation equation includes:

[0045]

[0046] Among them, H y The calibration position of the image acquisition unit, s x and s y The calibration position of the image acquisition unit is the standard position corresponding to the planar calibration unit. Let a be the transformation matrix of the position transformation equation. 12 a 22 a 14 a 24 are the coefficients of the transformation matrix.

[0047] Secondly, this application provides a chip surface height measuring device, which adopts the following technical solution: the device is applied to a chip surface height measuring system, the chip surface height measuring system comprising: an image acquisition unit for acquiring image information, a laser emitting unit for emitting laser lines, and a height calibration unit for calibrating height, the device comprising:

[0048] A laser line emitting module is used to control the laser emitting unit to emit a laser line to the location of the chip at a preset angle;

[0049] An image information acquisition module is used to control the image acquisition unit to acquire chip image information, the chip image information including laser line images;

[0050] The centroid position calculation module is used to select the laser line calculation region in the laser line image and calculate the centroid position of the laser line calculation region.

[0051] The surface height calculation module is used to substitute the centroid position into the chip height measurement equation to obtain the chip surface height.

[0052] Thirdly, this application provides a computer device that adopts the following technical solution: it includes a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executed as any of the chip surface height measurement methods described above.

[0053] Fourthly, this application provides a computer-readable storage medium that stores a computer program capable of being loaded by a processor and executing any of the above-mentioned chip surface height measurement methods.

[0054] In summary, this application has the following beneficial technical effects:

[0055] By controlling the laser emitting unit to emit a laser line onto the chip, and then using the image acquisition unit to acquire the image information of the laser line at the location of the unit, the surface height of the chip can be calculated by selecting the area and using the chip height measurement equation. By using a combination of image and laser, the measurement equipment does not need to be in direct contact with the chip substrate, thus enabling non-contact measurement of the chip surface height, which helps to reduce damage to the chip substrate. Attached Figure Description

[0056] Figure 1 This is a flowchart of the chip surface height measurement method in the embodiments of this application;

[0057] Figure 2 This is a schematic diagram of a camera combined with a laser measuring height in an embodiment of this application;

[0058] Figure 3 This is a schematic diagram of a laser line illuminating a calibration surface to select a calibration area in an embodiment of this application;

[0059] Figure 4 This is a schematic diagram of least squares fitting in an embodiment of this application;

[0060] Figure 5 This is a schematic diagram of the height calibration unit in an embodiment of this application;

[0061] Figure 6 This is a schematic diagram of the chip surface height measuring device in an embodiment of this application;

[0062] Figure 7 This is a schematic diagram used to illustrate a computer device in the embodiments of this application.

[0063] Reference numerals: 601, laser line emission module; 602, image information acquisition module; 603, centroid position calculation module; 604, surface height calculation module. Detailed Implementation

[0064] The following is in conjunction with the appendix Figure 1-7 This application will be described in further detail.

[0065] This application discloses a method for measuring the surface height of a chip. This method is applied to a chip surface height measurement system, allowing users to achieve non-contact measurement of the chip surface height. The method involves a laser emitting unit generating a laser line that illuminates the chip to be measured. An image acquisition unit then captures the image information of the laser line illuminating the chip. The system selects the calculation area of ​​the laser line in the image, determines the centroid of the calculation area, and substitutes it into a pre-fitted height measurement equation to calculate the actual height of the chip surface. The entire process uses laser irradiation and image acquisition to calculate the centroid position and obtain the chip surface height data, thus achieving non-contact measurement. The reason for requiring non-contact measurement is that contact measurement methods, when measuring high heights, may damage the chip substrate structure, potentially leading to chip damage and economic losses. To help reduce the occurrence of chip substrate structure damage, this application proposes a chip surface height measurement method.

[0066] Reference Figure 1 The method includes the following steps:

[0067] S10 controls the laser emitting unit to emit a laser line to the chip location at a preset angle.

[0068] Specifically, the system includes a laser emitting unit for emitting laser lines. The laser emitting unit can be any laser capable of emitting laser lines; no limitation is imposed here. In this embodiment, a solid-state laser is used as an example. A solid-state laser can generate laser lines or crosshairs with a width of approximately 0.2 mm. By controlling the solid-state laser to emit laser lines to the location of the chip, the surface height of the chip can be measured subsequently in conjunction with an image acquisition unit. The angle at which the laser emitting unit, i.e., the solid-state laser, emits the laser line is a pre-set fixed angle that remains constant throughout the chip measurement process. The specific angle of laser emission can be preset and determined by the user based on actual conditions; no limitation is imposed here.

[0069] S20, control the image acquisition unit to acquire chip image information, including laser line image.

[0070] Specifically, the system includes an image acquisition unit for acquiring image information. The image acquisition unit can be any device capable of capturing images, such as a camera, and is not limited here. In this embodiment, the image acquisition unit is described using a camera as an example. After the solid-state laser emits a laser line onto the chip, the camera is controlled to capture an image of the chip. The image of the chip includes the chip and the laser line image on the chip.

[0071] S30: Select the laser line calculation region in the laser line image and calculate the centroid position of the laser line calculation region.

[0072] Specifically, after the system acquires the laser line image on the chip, it selects a region of the laser line on the chip to obtain the laser line calculation area. Then, it calculates the centroid position of the laser line calculation area. The centroid position can be understood as the x-coordinate and y-coordinate of the centroid in a coordinate system. The centroid position can be calculated by weighted averaging of the laser line calculation areas. The method for selecting the laser line region on the chip can be either using the center of the laser line as the laser line calculation area, or selecting a specific location according to the user's actual needs; there are no restrictions here. The size of the laser line calculation area selection box needs to be greater than the width of the laser line. For example, in this embodiment, the width of the laser line generated by the solid-state laser is approximately 0.2mm, so the size of the laser line calculation area selection box needs to be greater than 0.2mm. For example, the selection box can be set as a square selection box with a side length of 1mm, or it can be set to other sizes according to the user's actual needs; there are no restrictions here.

[0073] S40, substitute the centroid position into the chip height measurement equation to obtain the chip surface height.

[0074] Specifically, by substituting the calculated position of the centroid, i.e. the values ​​of the x and y coordinates of the centroid in the coordinate system, into the pre-fitted chip height measurement equation, the chip surface height can be finally calculated.

[0075] It should be noted that the system may also include a drive structure. The camera and solid-state laser can be fixedly connected. The system can control the movement of the camera and solid-state laser by controlling the drive structure, so that the surface height of the chip can be measured in real time at different positions. The data measured by the laser and camera can be fed back to the system in real time. The system measures the change in surface height in real time, thereby realizing real-time position compensation. Real-time measurement can greatly save equipment debugging time.

[0076] In this application, a laser emitting unit is controlled to emit a laser line onto the chip, and an image acquisition unit is used to acquire the image information of the laser line at the location of the unit. After selecting the area, the surface height of the chip can be calculated using the chip height measurement equation. By combining image and laser, the measurement equipment does not need to be in direct contact with the chip substrate, thus enabling non-contact measurement of the chip surface height, which helps to reduce damage to the chip substrate.

[0077] In one embodiment, the chip surface height measurement system further includes: a plane calibration unit for calibrating the plane position, wherein the step of establishing the chip height measurement equation can be specifically performed as follows:

[0078] First, a position transformation equation is established based on the correspondence between the calibration position of the image acquisition unit and the standard position of the calibration position on the planar calibration unit. The purpose of establishing the transformation equation is to correct the position of the image acquisition unit, so that the laser line, selection box size, or position in the image captured by the image acquisition unit, i.e., the camera, are calculated under the standard position, thereby making the calculation results more accurate. Next, a position is pre-set, and the image acquisition unit, i.e., the camera, is moved to that position to acquire the actual position of the camera. Based on the actual position of the camera, the coordinate data of the actual position is substituted into the fitted position transformation equation to obtain the measurement standard position of the camera. Under the measurement standard position, the laser emission unit, i.e., the solid-state laser, is controlled to adjust its position and emit a laser line at a preset fixed angle towards the calibration surface of the height calibration unit. Then, the image acquisition unit is controlled to acquire the image of the laser line, for example, referring to... Figure 2 The system controls the laser to emit a laser line onto the calibration surface at a preset angle θ. Then, it controls a camera to capture an image containing the laser line above its position and transmits this image to the system for further processing. After acquiring the laser line image, the system selects several calibration regions along the laser line and calculates the centroid positions of these regions. The size of the selection frame and the number of calibration regions can be set by the user according to actual needs. The selection of calibration regions can be done by uniformly choosing them at fixed intervals along the laser line or by randomly choosing them. The user can determine the selection method according to their needs; there are no restrictions here. For example, referring to... Figure 3A laser line is emitted onto the calibration surface of the height calibration unit. An image is captured by a camera and transmitted to the system. The system processes the image, selecting six laser line calibration areas to calculate the centroid coordinates of the areas. The calculated centroid position is the plane position of the height calibration unit, formed by the x and y coordinates in the coordinate system. Then, based on the centroid's x and y coordinates and the coordinate calculation equation, the height of the centroid can be calculated, thus obtaining the three-dimensional coordinates of the centroid of the calibration area. The coordinate calculation equation can be calculated using trigonometric functions. For example, given the laser illumination angle θ and the centroid's x coordinate, the height z of the centroid can be obtained using trigonometric functions. The trigonometric function equation is as follows:

[0079] z = x · tanθ

[0080] Where x represents the abscissa of the centroid of the calibration area, θ is the angle between the laser line and the calibration surface, and z is the actual height of the centroid of the calibration area in the height calibration unit.

[0081] Finally, using the Gaussian plane equation and the obtained three-dimensional coordinates of several centroids, a chip height measurement equation can be fitted and generated. The Gaussian plane equation can be expressed as:

[0082] n1x + n2y + n3z + n4 = 0

[0083] Converted into matrix representation, it can be expressed as:

[0084]

[0085] Where x, y, and z represent the three-dimensional coordinates of the centroid of the calibration area, and n1, n2, n3, and n4 are the coefficients of the Gaussian plane equation. Using multiple centroid three-dimensional coordinates, the coefficients of the Gaussian plane equation can be calculated, thus fitting and generating a height measurement equation. The fitting equation can be achieved using the least squares method, for example, referring to... Figure 4 This is a schematic diagram of fitting using the least squares method.

[0086] It should be noted that the chip height measurement equation is a pre-fitted equation established by the user. When actually measuring the chip surface height, the user can directly use the pre-established chip height measurement equation after obtaining data from the camera and laser, and substitute the coordinate data to obtain the chip surface height, that is, obtain the data that the user needs to measure.

[0087] In this application, the image acquisition unit's position is corrected by transforming its coordinate system, allowing it to acquire image information in a reference coordinate system. This improves the accuracy of image information acquisition and consequently enhances the accuracy of chip surface height measurement. A laser line is emitted from the laser emission unit at the standard position of the image acquisition unit, and the centroid of the laser line on the standard height calibration unit is obtained. This allows for the calculation of the actual height of the laser line on the calibration surface. A height measurement equation is generated by fitting the actual position of the laser line on the height calibration unit, facilitating the calculation of chip surface height in practical applications. In practical applications, the laser emission unit calibration eliminates the need for direct contact between the measuring device and the chip substrate, enabling non-contact measurement and reducing the risk of damage to the chip substrate.

[0088] In one embodiment, considering that when fitting the Gaussian plane equation using the three-dimensional coordinates of the centroid, the limited data of the centroid may result in insufficient accuracy and limited applicability of the height measurement equation generated by the fitting. Therefore, the chip surface height measurement system further includes: a driving unit for synchronously moving the image acquisition unit and the laser emission unit; the calibration surface includes calibration surfaces of different heights; after calculating the three-dimensional coordinates of the centroid of the calibration area based on the centroid position of the calibration area and the preset coordinate calculation equation, the following steps can also be performed:

[0089] The control drive unit moves the image acquisition unit and the laser emission unit sequentially. The image acquisition unit can be understood as a camera, and the laser emission unit as a solid-state laser. The camera and laser are fixedly connected, and the laser moves synchronously when the drive unit moves the camera. The height calibration unit can be a stepped two-dimensional calibration plate, for example, referring to... Figure 5 The calibration surface of the height calibration unit can be a calibration surface of different heights, which can be understood as step surfaces of different heights on a stepped two-dimensional calibration plate. By controlling the drive unit to move the camera and laser sequentially, laser line images on different step surfaces can be obtained. Several calibration areas are selected from the laser line images of different step surfaces, and the two-dimensional coordinates of the centroid are calculated by weighted averaging. The height of the centroid of the calibration area is calculated using the coordinate calculation equation to obtain the three-dimensional coordinates of the centroid. The same number of centroids can be obtained on the calibration surface at the same height. Multiple sets of three-dimensional coordinate data of the centroid can be obtained on different step surfaces, i.e., calibration surfaces of different heights. Then, the multiple sets of three-dimensional coordinate data of the centroid are substituted into the Gaussian plane equation to calculate the parameters of the Gaussian plane equation, so that the chip height measurement equation can be generated by fitting. The method for fitting and calculating the parameters of the Gaussian plane equation can be the least squares method.

[0090] In this application, the height calibration unit includes multiple calibration surfaces with different heights. By moving the laser emitting unit, a laser line is emitted from the calibration surfaces at different heights, capturing multiple sets of calibration areas and calculating the actual position of the centroid of the calibration area. The actual position is used to fit and generate a height measurement equation, which can be used to calculate the chip surface height in practical applications. By calculating the fitting equation at the centroid positions of the multiple calibration surfaces at different heights in the height calibration unit, the fitted equation result can be closer to the actual situation, improving the accuracy of chip surface height measurement in practical applications.

[0091] In one embodiment, establishing a position transformation equation based on the correspondence between the calibration position of the image acquisition unit and the standard position of the calibration position in the planar calibration unit can be specifically performed as follows:

[0092] First, the calibration position of the image acquisition unit is obtained, which can be understood as the actual position of the camera when taking a picture. Then, the camera captures the planar calibration information of the planar calibration unit, which includes the standard position corresponding to the camera's calibration position. Finally, based on the camera's actual position and its standard position in the planar calibration unit, a position transformation equation can be obtained. This transformation equation can be:

[0093]

[0094] Among them, H y For the calibration position of the image acquisition unit, s x and s y The calibration position of the image acquisition unit is the standard position corresponding to the planar calibration unit. Let a be the transformation matrix of the position transformation equation. 12 a 22 a 14 a 24 These are the coefficients of the transformation matrix.

[0095] It should be noted that in this embodiment, the camera is a movable camera. By moving the camera, there can be multiple actual positions of the camera and standard positions corresponding to the actual positions of the cameras. The coefficients in the transformation matrix can be calculated by multiple sets of data, and finally the position transformation equation is generated. Therefore, the calibrated position of the camera can be understood as a set of data of the actual position obtained by the camera after a series of movements, and the standard position corresponding to the calibrated position can also be understood as a set of data of the standard position. The position transformation equation is generated by fitting the data set.

[0096] In addition, the calibration information of the planar calibration unit also includes standard size information. The camera can calibrate the size of the image captured by the camera by shooting the planar calibration information. At the same time, it can also realize the distortion correction of the camera, so that the size in the field of view of the camera is fixed and will not change due to changes in the shooting angle or field of view, thus improving the accuracy of measuring the height of the chip with the camera.

[0097] In this application, a transformation equation is established to link the actual coordinates of the camera with the reference coordinates of the plane calibration unit. This allows for measurement and position calculation in a standard reference coordinate system during subsequent measurements, which helps to make the chip surface height measurement more accurate.

[0098] In one embodiment, considering that the measurement data may be biased if the camera is not calibrated beforehand when actually measuring the height of the chip surface, the following steps can be performed before controlling the laser emitting unit to emit a laser line to the chip location at a preset angle:

[0099] First, the image acquisition unit, i.e., the camera, captures the actual measured position of the chip. Then, based on the pre-obtained position transformation equation, the actual measured position of the chip is converted into the standard measurement position of the chip. After that, under the standard measurement position of the chip, the laser emission unit is controlled, i.e., the laser emits a laser line to the chip location at a preset fixed angle.

[0100] In this application, before using laser measurement to actually measure the height of the chip surface, the position of the image acquisition unit is calibrated using a position transformation equation. This ensures that the coordinates of the image acquisition unit are in the standard reference coordinate system after each movement, making the final measured height result more accurate and improving the precision of chip surface height measurement.

[0101] Figure 1 This is a flowchart illustrating a chip surface height measurement method in one embodiment. It should be understood that, although... Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows; unless explicitly stated otherwise, there is no strict order requirement for the execution of these steps, and they can be executed in other orders; and Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0102] Based on the above method, this application also discloses a chip surface height measuring device.

[0103] Reference Figure 6 The device includes the following modules:

[0104] The laser line emitting module 601 is used to control the laser emitting unit to emit a laser line to the location of the chip at a preset angle.

[0105] Image information acquisition module 602 is used to control the image acquisition unit to acquire chip image information, including laser line images;

[0106] The centroid position calculation module 603 is used to select the laser line calculation area in the laser line image and calculate the centroid position of the laser line calculation area.

[0107] The surface height calculation module 604 is used to substitute the centroid position into the chip height measurement equation to obtain the chip surface height.

[0108] In one embodiment, the chip surface height measurement system further includes: a plane calibration unit for calibrating the plane position; a surface height calculation module 604, which is further configured to: establish a position transformation equation based on the correspondence between the calibration position of the image acquisition unit and the standard position of the calibration position in the plane calibration unit; acquire the preset actual position of the image acquisition unit; obtain the measurement standard position of the image acquisition unit based on the preset actual position and the position transformation equation; control the laser emission unit to emit a laser line at a preset angle towards the calibration surface of the height calibration unit at the measurement standard position; control the image acquisition unit to acquire the image of the laser line; select several calibration areas of the laser line in the image of the laser line and calculate the centroid positions of several calibration areas; calculate the three-dimensional coordinates of the centroid of the calibration area based on the centroid positions of the calibration areas and the preset coordinate calculation equation; and use the Gaussian plane equation to fit and generate a chip height measurement equation based on the three-dimensional coordinates of the centroids of several calibration areas.

[0109] In one embodiment, the chip surface height measurement system further includes: a driving unit for synchronously moving the image acquisition unit and the laser emission unit; the calibration surface includes calibration surfaces at different heights; a surface height calculation module 604, which is also used to control the driving unit to move the image acquisition unit and the laser emission unit sequentially; control the laser emission unit to emit laser lines at preset angles on the calibration surfaces at different heights; control the image acquisition unit to acquire images of the laser lines on the calibration surfaces at different heights; select several calibration areas of the laser lines in the laser line images, calculate the centroid positions of several calibration areas, and obtain multiple sets of centroid positions of calibration areas on the calibration surfaces at different heights; calculate the three-dimensional coordinates of the centroids of the calibration areas based on the centroid positions of the calibration areas and preset coordinate calculation equations, and generate the three-dimensional coordinates of the centroids of multiple sets of calibration areas on the calibration surfaces at different heights; and use the Gaussian plane equation to fit and generate a chip height measurement equation based on the three-dimensional coordinates of the centroids of multiple sets of calibration areas.

[0110] In one embodiment, the surface height calculation module 604 is further configured to obtain the calibration position of the image acquisition unit; control the image acquisition unit to collect the plane calibration information of the plane calibration unit, the plane calibration information including the standard position corresponding to the calibration position of the image acquisition unit; and generate a position transformation equation based on the calibration position of the image acquisition unit and the standard position corresponding to the calibration position.

[0111] In one embodiment, the laser line emitting module 601 is further configured to acquire the actual measurement position of the chip from the chip image acquired by the image acquisition unit; convert the actual measurement position of the chip into a standard measurement position of the chip according to the position transformation equation; and control the laser emitting unit to emit a laser line to the chip location at a preset angle, including: controlling the laser emitting unit to emit a laser line to the chip location at a preset angle under the standard measurement position of the chip.

[0112] In one embodiment, the surface height calculation module 604 further includes a preset coordinate calculation equation: z = x · tanθ, where x represents the abscissa of the centroid of the calibration area, θ is the angle between the laser line and the calibration surface, and z is the actual height of the centroid of the calibration area in the height calibration unit.

[0113] In one embodiment, the surface height calculation module 604 further includes a position transformation equation:

[0114]

[0115] Among them, H y For the calibration position of the image acquisition unit, s x and s y The calibration position of the image acquisition unit is located at the standard position corresponding to the planar calibration unit. Let a be the transformation matrix of the position transformation equation. 12 a 22 a 14 a 24 are the coefficients of the transformation matrix.

[0116] The chip surface height measuring device provided in this application embodiment can be applied to the chip surface height measuring method provided in the above embodiment. For relevant details, please refer to the above method embodiment. The implementation principle and technical effect are similar, and will not be repeated here.

[0117] It should be noted that the chip surface height measuring device provided in this embodiment is only illustrated by the division of the above-mentioned functional modules / units when measuring chip surface height. In practical applications, the above functions can be assigned to different functional modules / units as needed, that is, the internal structure of the chip surface height measuring device can be divided into different functional modules / units to complete all or part of the functions described above. Furthermore, the implementation method of the chip surface height measuring method provided in the above-mentioned method embodiments and the implementation method of the chip surface height measuring device provided in this embodiment belong to the same concept. The specific implementation process of the chip surface height measuring device provided in this embodiment is detailed in the above-mentioned method embodiments and will not be repeated here.

[0118] This application also discloses a computer device.

[0119] Specifically, such as Figure 7 As shown, the computer device can be a desktop computer, laptop computer, handheld computer, or cloud server, etc. The computer device may include, but is not limited to, a processor and memory. The processor and memory can be connected via a bus or other means. The processor can be a Central Processing Unit (CPU). The processor can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, graphics processing units (GPUs), embedded neural network processing units (NPUs) or other dedicated deep learning coprocessors, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips.

[0120] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the methods in the above embodiments of this application. The processor executes various functional applications and data processing by running the non-transitory software programs, instructions, and modules stored in the memory, thereby implementing the methods in the above embodiments. The memory may include a program storage area and a data storage area, wherein the program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created by the processor, etc. Furthermore, the memory may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0121] This application also discloses a computer-readable storage medium.

[0122] Specifically, the computer-readable storage medium is used to store a computer program, which, when executed by a processor, implements the methods described in the above-described method embodiments. Those skilled in the art will understand that implementing all or part of the processes in the methods described in the above-described embodiments of this application can be accomplished by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0123] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A method for measuring the surface height of a chip, characterized in that: The method is applied to a chip surface height measurement system, which includes: an image acquisition unit for acquiring image information, a laser emission unit for emitting laser lines, and a height calibration unit for calibrating height. The method includes: The laser emitting unit is controlled to emit a laser line to the location of the chip at a preset angle. The image acquisition unit is controlled to acquire chip image information, including laser line images; Select the laser line calculation region in the laser line image and calculate the centroid position of the laser line calculation region; Substitute the centroid position into the chip height measurement equation to obtain the chip surface height; The chip surface height measurement system further includes: a plane calibration unit for calibrating the plane position, and the steps for establishing the chip height measurement equation include: Based on the calibration position of the image acquisition unit, a position transformation equation is established with the correspondence between the calibration position and the standard position of the plane calibration unit; The image acquisition unit obtains the preset actual position; The measurement standard position of the image acquisition unit is obtained based on the preset actual position and the position transformation equation; At the standard measurement position, the laser emitting unit is controlled to emit a laser line toward the calibration surface of the height calibration unit at the preset angle; The image acquisition unit is controlled to acquire an image of the laser line; In the image of the laser line, several calibration regions of the laser line are selected, and the centroid positions of the several calibration regions are calculated; The three-dimensional coordinates of the centroid of the calibration area are calculated based on the centroid position of the calibration area and the preset coordinate calculation equation. The chip height measurement equation is generated by fitting the three-dimensional coordinates of the centroids of several calibration regions using the Gaussian plane equation.

2. The method according to claim 1, characterized in that: The chip surface height measurement system further includes: a driving unit for driving the image acquisition unit and the laser emission unit to move synchronously, and the calibration surface includes calibration surfaces of different heights; After calculating the three-dimensional coordinates of the centroid of the calibration region based on the centroid position of the calibration region and a preset coordinate calculation equation, the method further includes: The driving unit is controlled to move the image acquisition unit and the laser emission unit sequentially. The laser emitting unit is controlled to emit laser lines at preset angles on calibration surfaces at different heights; The image acquisition unit is controlled to acquire images of the laser line at different heights on the calibration surface; In the image of the laser line, several calibration regions of the laser line are selected, the centroid positions of several calibration regions are calculated, and multiple sets of centroid positions of the calibration regions at different heights are obtained. The three-dimensional coordinates of the centroid of the calibration area are calculated based on the centroid position of the calibration area and the preset coordinate calculation equation, and multiple sets of three-dimensional coordinates of the centroid of the calibration area are generated on the calibration surface at different heights. The chip height measurement equation is generated by fitting the three-dimensional coordinates of the centroids of multiple calibration regions using the Gaussian plane equation.

3. The method according to claim 1, characterized in that: The step of establishing a position transformation equation based on the correspondence between the calibration position of the image acquisition unit and the standard position of the calibration position in the planar calibration unit includes: Obtain the calibration position of the image acquisition unit; The image acquisition unit is controlled to acquire the plane calibration information of the plane calibration unit, and the plane calibration information includes the standard position corresponding to the calibration position of the image acquisition unit; The position transformation equation is generated based on the calibration position of the image acquisition unit and the standard position corresponding to the calibration position.

4. The method according to claim 1, characterized in that: Before controlling the laser emitting unit to emit a laser line to the chip location at a preset angle, the method further includes: The image acquisition unit acquires the actual measured position of the chip in the chip image. According to the position conversion equation, the actual measured position of the chip is converted into the standard measured position of the chip; The step of controlling the laser emitting unit to emit a laser line to the chip location at a preset angle includes: At the chip measurement standard position, the laser emitting unit is controlled to emit a laser line to the chip location at a preset angle.

5. The method according to claim 1, characterized in that: The preset coordinate calculation equations include: in, The x-coordinate of the centroid of the calibration region is represented by the following: The angle between the laser line and the calibration surface. The centroid of the calibration region is located at the actual height of the height calibration unit.

6. The method according to claim 3, characterized in that: The position transformation equation includes: in, The calibration position of the image acquisition unit. and The calibration position of the image acquisition unit is the standard position corresponding to the planar calibration unit. Let be the transformation matrix of the position transformation equation. are the coefficients of the transformation matrix.

7. A chip surface height measuring device, characterized in that: The device is applied to a chip surface height measurement system, which includes: an image acquisition unit for acquiring image information, a laser emission unit for emitting laser lines, and a height calibration unit for calibrating height. The device further includes: A laser line emitting module (601) is used to control the laser emitting unit to emit a laser line to the location of the chip at a preset angle. Image information acquisition module (602) is used to control the image acquisition unit to acquire chip image information, the chip image information including laser line image; The centroid position calculation module (603) is used to select the laser line calculation region in the laser line image and calculate the centroid position of the laser line calculation region; A surface height calculation module (604) is used to substitute the centroid position into the chip height measurement equation to obtain the chip surface height; The chip surface height measurement system also includes: a plane calibration unit for calibrating the plane position, a surface height calculation module (604), and a position transformation equation established based on the calibration position of the image acquisition unit and the correspondence between the calibration position and the standard position of the calibration position in the plane calibration unit; acquiring the preset actual position of the image acquisition unit; obtaining the measurement standard position of the image acquisition unit based on the preset actual position and the position transformation equation; controlling the laser emission unit to emit a laser line at a preset angle to the calibration surface of the height calibration unit at the measurement standard position; controlling the image acquisition unit to acquire the image of the laser line; selecting several calibration areas of the laser line in the image of the laser line and calculating the centroid positions of several calibration areas; calculating the three-dimensional coordinates of the centroid of the calibration area based on the centroid positions of the calibration areas and the preset coordinate calculation equation; and using the Gaussian plane equation, fitting the three-dimensional coordinates of the centroids of several calibration areas to generate a chip height measurement equation.

8. A computer device, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executed according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer program is stored that can be loaded by a processor and executed according to any one of claims 1 to 6.

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